Dynamic and Permanent Lease Types

The lease type determines whether the lease
policy applies to the IP addresses you are configuring. During initial server
configuration, DHCP Manager allows you to select either dynamic or permanent
leases for the addresses you are adding. If you configure the DHCP server
with the dhcpconfig command, leases are dynamic.

When an IP address has a dynamic lease, the DHCP
server can manage the address. The DHCP server can allocate the IP address
to a client, extend the lease time, detect when the address is no longer in
use, and reclaim the address. When an IP address has a permanent
lease, the DHCP server can only allocate the address. The client
then owns the address until explicitly releasing the address. When the address
is released, the server can assign the address to another client. The address
is not subject to the lease policy as long as the address is configured with
a permanent lease type.

When you configure a range of IP addresses, the lease type you select
applies to all the addresses in the range. To get the most benefit from DHCP,
you should use dynamic leases for most of the addresses. You can later modify
individual addresses to make them permanent, if necessary. However, the total
number of permanent leases should be kept to a minimum.